1. Field of the Invention
The present invention relates to a modular jack mounted to an apparatus such as a notebook type personal computer, a game machine or the like and mated with a modular plug corresponding thereto.
2. Description of the Related Art
A modular jack of this kind is for connecting a modular plug from a telephone network or an LAN network and is provided with a casing made of synthetic resin having an insertion recessed portion for inserting and drawing a modular plug. At inside of the insertion recessed portion, there is contained a contact pin for being brought into contact with a contact of the modular plug.
Normally, a portion of the casing, particularly, a surrounding of an insertion opening communicating with the insertion recessed portion, is surrounded by a shell made of a metal to thereby achieve electromagnetic shielding for the contact pin at inside of the insertion recessed portion.
Meanwhile, it is not so much preferable to expose a shell made of a metal formed by normally sheet metal drawing to outside in view of its appearance. Further, there is a concern that a foreign matter is brought into touch with the exposed shell and noise is generated.
The present invention has been carried out in view of the above-described problem and it is an object of the invention to provide a modular jack excellent in appearance and electromagnetic shielding performance.
In order to achieve the above-described object, according to the first object of the invention, there is provided a modular jack characterized in including a casing having an insulating performance and having an insertion recessed portion for a modular plug opened in a front direction; a shell made of a metal for electromagnetic shielding including a front plate covering a front face of the casing and partitioning an insertion opening for the modular plug communicating with the insertion recessed portion at the front plate; and an insulating cover including a front plate covering the front plate of the shell and partitioning an insertion opening for the modular plug communicating with the insertion recessed portion at the front plate, wherein the insertion opening of the insulating cover is made smaller than the insertion opening of the shell such that an edge portion of the insertion opening of the shell is prevented from being exposed by an edge portion of the insertion opening of the insulating cover.
According to the invention, in a state in which the edge portion of the insertion opening of the front plate of the shell is not exposed, the front plate of the shell is covered by the insulating cover and therefore, the appearance is excellent. Further, a foreign matter is prevented from being brought into contact with the shell and electromagnetic shielding is ensured.
According to the second aspect of the invention, there is provided the modular jack according to the first aspect, characterized in that the shell further includes side walls extended from the front plate and provided along corresponding side walls of the casing and the insulating cover further includes side walls extended from the front plate and provided along the corresponding side walls of the shell. In this case, a range of covering the shell by the insulating cover can be widened and therefore, a foreign matter can be prevented from being brought into contact with the shell further firmly.
According to the third aspect of the invention, there is provided the modular jack according to the second aspect, characterized in that the corresponding side walls of the shell and the insulating cover are unitarily locked by locking portions provided at the corresponding side walls of the casing. In this case, the structure can be simplified and the fabrication cost can be made inexpensive.